Hey I think it looks pretty good! I like the spikes added at the top of the staff. If I were to do this differently, I'd probably make the staff a little longer. Do you have a leftover banner pole? Those tend to work pretty well. The shield is cool, like a battle priest. You could also do the 'more magic' route, and maybe convert him holding an orb, or a familiar nearby on a base.
Overall I like it! The feathers and the chain near his helmet adds to the model, and it makes him appear to be moving or in the midst of spell casting -- good job.